Air compressor



March l5, 1932. o. E. BLACK AIR COMPRESSOR Filed Dec. 18,'1929 2 Sheets-Sheet l INVENIOR 'ons ,BFM

'3U/mw* A M 774i ATTORNEY O. E. BLACK March 15, 1932.

AIR COMPRESSOR Iii/.uvm

0%' ATTORNEY l Patented Mar. 15, 1932 UNITED STATES PATENT OFFICE OTTO E. BLACK, OF DAYTON, OHIO, .ASSIGNOR TO THE DAYTON .AIR COMPRESSOR COM- PANY, 01?" DAYTON, OHIO, .A CORPORATION' OF OHIO .AIR COMPRESSOR Application led December 18, 1929. Serial No. 414,921.

This invention relates to new and useful improvements in air compressors. i

It is one of the principal objects of my invention to provide an air compressor which is simple and compact in construction and smooth, easy and powerful in operation.

By the elimination of the crankshaft and all bearings except the main one, together with other parts, I have provided an eXtremely simple construction in which friction is reduced to the minimum. There is also less vibration, resulting in a quieter motion of the rotating and reciprocating parts.

My compressor by insuring a non-pulsating flow of air from its four cylinders, lends itself excellently for use with blowers, paint sprayers and the like. It maybe operative with two cylinders, however, and may be converted from a single to a multi-stage type. The pistons really iioat in the cylinders, so slight is the friction created by the wobble plate and short connecting rod structure.

It is another object of my invention to pron duce an air compressor which combines greater power with a minimum of weight as .compared with other reciprocating type compressors.

Other important and incidental objects will be brought out in the following specication and particularly set forth in the subjoined claims.

In the accompanying drawings illustratv ing my invention, Figure 1 is a longitudinal sectional view taken through my improved air compressor. Figure 2 is an end view of the compressor cylinders. Figure 3 is a cross sectional view taken through the compressor on the line 3-3 of Figure 1. And Figure 4 is a sectional view taken through one cylinder 40 head on the line 4-4 of Figure 2.

Referring to the accompanying drawings for a detailed description of my invention, the numeral 1 designates a motor frame that is mounted on a base 2. The numeral 3 designates the motor end frame to which a rotor housing 4 is secured by through bolts 5.

A plurality of cylinders 6, in this instance four, are radially secured by through bolts 7 to four annular bosses 8 which are spaced an equal distance apart, and in circumferenwithin its transverse slot 30.

tial alinement with each other on the outer face of the rotor casing 4. These cylinders, which communicate with the interior of the casing, are formed with iins 9 for cooling purposes.

v Secured to the outer end of each cylinder 6 is a plate 10 against which a gasket 11 is pressed by a ported head 12 when the nuts ,13 are tightened on the through bolts 7 that pass through holes in said head, gasket and A00 plate (see Figure 1).

Freeto reciprocate within each cylinder 6 is a piston 14 provided with sealing rings 15. The pistons 14 practically float in their respective cylinders because of their movement by the anti-friction means now to be described.

Referring to Figures 1 and 3, the numeral 16 designates an armature shaft that projects into the rotorl housing 4 from a bearing 17 on the motor end frame 3. Secured to that portion of the shaft 16 within the rotor housing, by a key such as the Woodruff key 18, is a sleeve 19. The latter is formed on its outer end with an annular groove 2O to receive an endless wick 21'. This enters an oil reservoir 22 at! the bottom of the rotor casing to raiseV oil therefrom and splatter it to the moving parts now to be described.

The inner end of the sleeve 19 is formed with a boss 22a whose outer periphery is inclined at an angle of approximately 12 to the axis 'of the sleeve as shown in Figure 1. Pressed or otherwise tightly secured on the inclined periphery of the boss 22a, against a shoulder 23 on its inner end, is the inner race member 24 of a double row ball bearing 25.

Disposed around the race member 24 of the bearing 25 are two rolls of balls 26 upon 'which an outer race member 27 is free to move. This race member is pressed or otherwise tightly secured on a wobble plate 28 against a shoulder 29 thereon. p

In the present instance the wobble plate 28 is formed with four radial arms, each one of which has a transverse slot 30 and an axial hole 3l. Each hole 31 is adapted to receive a'pin 32 by which the inner end of a link 33 is pivotally secured to a wobble plate arm 29 To the outer end of each link 33 there is secured, by a pin 34, the bifurcated inner end of a short connecting rod 35 which is attached by a wrist pin 36 to a respective piston 14.

The rotation of the armature shaft 16 by the electric motor within the frame 1, will cause the sleeve 19 and inner race 24 of the bearing 25 to rotate with it. The plate 28 will follow this rotation of the inner bearing race 24 sufficiently to wobble on it, thereby communicating in a quiet, effective way a reciprocating movement to the pistons 14.

All of the advantages of long connecting rods in the way of reducing friction are possessed by the short connecting rods 35 through their connection to the wobble plate. By the employment of the latter, which has the eX- tent of travel indicated by the dotted line a-a in Figure 1, I gain simplicity and co1n pactness in the compressor unit, as well as in quietness and additional power, over the present Crank shaft type of compressors.

Air for compression is admitted to the cylinder heads 12 through ports 36 (see Figures 1 and 4). The inlet port 36 is separated from an exhaust port 37 in each cylinder head 6 by a short web 38 to which the outer wall of the head curves to form with the web a Y in cross section as shown in Figure 4.

Formed in the inner wall of each cylinder head 6 for communication with the inlet port 36, is a central guide hole 39 and surrounding air inlet holes 40 (see Figure 4). These holes terminate in a recess 41 in the head that registers with a hole in the gasket 11 and a similar recess 42 in the plate 10. From the inner bottom portion of the recess 42 an air inlet hole 48 in said plate leads to the interior of the cylinder 6.

Within the space formed by the recesses 41 and 42 a disc valve 44 is free to be, moved outwardly by the air within the cylinder on the compression stroke of the piston to close the air inlet holes 40. In this movement the valve is guided by a center pin 45 in the guide hole 39 within the head. On the suction stroke of the piston, the valve 44 is restrained from closing the hole 43 through the engagement with the plate 1() of a flange 46 on an inner pin 47 that is free to move in a guide hole within said plate. (See Figure 4.)

rIhe discharge of air from each cylinder 6 is controlled by a disc valve 48 which, on the suction stroke of the piston, closes an exhaust air hole 49 in the plate 10. The latter communicates at its outer end with a recess 50 in the plate, that registers with a hole in the gasket 11 and a recess 51 in the head 6. These two recesses and the hole in the gasket provide for the valve 48 a chamber that communicates with the exhaust port 37 through holes 52. (See Figure 4.)

An axial pin 53 that projects from the valve 48 into a. hole 54 in the plate 10, guides the valve, while a flange 55 on an outer axial pin 56 that enters a hole in the head 6, is adapted to engage the latter to prevent a closure of the holes 52 on the outward movement of the valve.

If desired, the outlet ports 37 of all the cylinders 6 may be connected by the following means to one main discharge line into which the air will be forced by the pistons in a strong, non-pulsating flow. Referring to Figure 2, the numeral 56 designates a U- shaped manifold that terminates at one free end in an angular extension 57. The latter is formed in its front end with a tapped hole which receives the left thread end of a con necting nipple 58. The right thread end of this nipple is adapted to be screwed into the tapped discharge end 37 of the head 6 of the cylinder on the extreme right in Figure 2.

rI`he ends of the U portion 56 of the manifold are adapted to be secured by left and right thread nipples 59 and 60 to the two middle cylinders in Figure 2, While the left cylinder in that ligure is connected by a left and right thread nipple 61 to the inner mid- ,dle tapped portion of the U-shaped portion of the manifold. The latter has a tapped dis charge boss 62 formed on its outer middle portion for connection with a main discharge line (not shown).

.Vhile I have illustrated the above manifold means for concentrating in one main discharge line, the air compressed in the four cylinders 6, any other suitable discharge means may be provided for this purpose.

While I have shown my invention as applied to air compressors, it is equally well adapted for use in air pumps.

I-Iaving described my invention, I claim:

Mechanism for converting rotary into reciprocating motion, comprising a rotary shaft, a sleeve secured on said shaft, a boss on. said sleeve with a periphery inclined in relation to the axis of the latter, an inner race member secured to the inclined periphery of the boss, an outer race member, balls between said race members, a wobble plate tightly fitted on the outer race member, arms on said wobble plate, reciprocating elements at substantially right angles to said arms, radial pins in the latter connected by the said pins and the reciprocating elements to reciprocate the latter when the shaft is rotated.

In testimony whereof I have hereunto set my hand this 14th day of December, 1929.

OTTO E. BLACK. 

